NTSB examination: Fracht has lost due to incorrect weight data

The incident

ON 6, 2024, approximately 2135 local time, the President of the US container, Eisenhower, drifted about 94 miles south of Oakland, California, and was waiting for an order when the crew found that 23 ship containers were lost overboard. None of the lost containers wore dangerous materials. There were no injuries and no pollution was reported. The damage to the container and the value of the lost freight was estimated at over 735,000 USD.

analysis

On February 6, the container President Eisenhower drifted around 94 miles from the port of Oakland in the Pacific when the crew was lost overboard 23 shipping containers from Bay 42. The crew then found that another 10 containers were damaged. Four days before the victim, Longshoremen container in Bay 42 had invited each container provided by the booking intermediary according to a freight load plan developed by the ship planners.

According to the victim, however, the booking agent found that an administrative error – in which the load weights for 39 containers were entered incorrectly – were significantly subjected to the VGMS for the 39 containers that were significantly subjected to the loading plan. The actual VGM for the 39 containers was 18.3 to 22.2 tons larger than the VGM used to develop the freight load plan. Of these 39 containers, 20 were invited to stacks in stacks in Bay 42. Ten of the containers with a false VGM on the loading plan were loaded on the back side of Bay 42, where the container loss occurred.

The actual weight of these ten containers was between 25.1 and 28.3 tons, which led to container stacking weights that exceeded the maximum stack of weight in the CSM of the company company by up to 26% (see Table 1). Since the charge plan for Bay contained 42 inaccurate VGMS, the stacking weights exceeded the allowance of the CSM, and the forces acting on both containers were larger than expected.

Since the containers were not wrong on the loading plan, the container stacks on the back side of Bay 42 were accidentally arranged with heavier containers in the upper levels and increasingly lighter containers towards the lower levels. This arrangement caused the stack to have a higher center of gravity than stacks that were arranged with the heaviest containers on the deck and increasingly lighter containers – as they were attributed as normal layer.

A normal stratification is preferred because it creates a stack of containers with the lowest possible focus. The freight safety equipment (twist locks and whip) in a reverse container stack is exposed to increased forces from the ship movement compared to sea. Therefore, the burden of containers in overweight and reverse stacks in Bay 42 increased the probability of failure of freight curing devices. According to the victim, the booking agent has changed its procedures and the booking system to prevent this type of input error from occurring in the future.

Since the freight loading plan was created with inaccurate data, it showed that the stacking weights on the back side of Bay 42 were within the maximum total pile weight restrictions that were prescribed in the CSM of the company company. The VGM The container was not verified at the terminal, and there were no problems during the charging processes. In addition, the recorded draft was within the 0.2 meter (0.7 feet) of acceptable variance or the “correction factor” compared to the calculated draft in the cargo and stability software from freight.

The expected middle design from the freight stability and charging software, when President Eisenhower Los Angeles left, was 9.62 meters (31.6 feet) with a calculated shift of 72,351 tons. In this loading condition, the tons of dive in the ship was about 93 (ie it would require a further 93 tons of weight to increase the middle design of the ship by 1 centimeter). Due to the non -reported container weights in the loading plan, there were about 835 tons of additional freight, which were not taken into account in the design calculations, load on bays 42 and 30).

Based on the charging conditions, the additional freight weight would have increased the middle design of the President Eisenhower by about 9 centimeters or 0.09 meters and led to a calculated mean design of 9.71 meters (31.9 feet). This was closer to the recorded middle design of 9.75 meters (32.0 feet) before the ship left Los Angeles, but the difference was still within the permissible correction factor of 0.2 meters. Therefore, there was no signs that the container stacks in Bay 42 were overweight during the charging process or while preparing for the departure of Los Angeles.

According to the victim, the ship operator found that the overweight and reverse container stacks exceeded the calculated “whip forces”, which caused the load equipment to fail.

As invited after departure from Los Angeles, some stacks for Bay 42 had exceeded the maximum permissible stacking weight of the CSM, and if known, the ship could not have sailed. Nevertheless, the ship successfully traveled from Los Angeles to Oakland (about 4 days) without any problems. In addition, a crew member had inspected the lashes of the containers after the ship had arrived outside the port of Oakland and found nothing intact. During the day, the ship drifts as he was waiting for entry to the port of Oakland, and increased the wind and the seas that the ship rolled at 18 °.

The adverse weather thresholds did not meet the weather and sea conditions in the SMS of the company company, and in the SMS, CSM or Onboard routing monitoring software, no rolling limit was prescribed, so that the crew did not take any measures to tackle the rolling. However, the 18º rolls were significantly higher than the vessel on the transit (maximum 5 °). According to the victim, the classification company found a slaughter damage and socket damage, which indicates that the whipping was overloaded and freely pulled.

The increased roller size of seases would have increased the compression forces that act on the containers within the stacks, and the shelves acting on the load disc equipment until the equipment failed, which led to damage and loss of containers.

Download the report here